The invention relates to a cartridge for at least two flowable components in accordance with the preamble of claim 1.
Cartridges for at least two flowable components having a filling end and a discharge end, with a component outlet being arranged at the discharge end, have already been marketed for some time by the applicant. These cartridges have a first storage chamber for a first component having a first inner wall extending between the filling end and the discharge end and having a first filling opening arranged at the filling end and also have a second storage chamber for a second component having a second inner wall extending between the filling end and the discharge end and having a second filling opening arranged at the filling end. The first and second storage chambers are connected to one another by means of a connection web. The first filling opening and the first inner wall are designed so that a first piston can be inserted into the first storage chamber such that it sealingly closes the first storage chamber. The second filling opening and the second inner wall are designed so that a second piston can be inserted into the second storage chamber such that it sealingly closes the second storage chamber. The first and second inner walls each have a bead running fully over the periphery in the region of the first and second filling openings by means of which bead the first and second pistons can be held captively, that is without risk of loss, after the insertion into the first and second chambers. The beads therefore prevent the piston from being able to slip out of the storage chambers after the insertion via the filling openings.
These cartridges are manufactured by means of an injection molding process, with a core required for the formation of the storage chambers and of the beads being pulled out through the filling openings after the opening of the injection tool without the use of pushers or of ejection pins or with the cartridge being removed from the core. A so-called forced demolding therefore takes place so that an inexpensive manufacture of the cartridges is possible. On the forced demolding of the cartridges in accordance with the prior art, permanent deformations of the beads can occur, with burrs being able to be formed which may result in damage to the pistons on the insertion of the pistons into the storage chambers. Pistons damaged in this manner can no longer reliably close the storage chambers so that, on the one hand, the components can be discharged past the pistons via the filling openings and, on the other hand, the components can come into contact with air, which can result in drying out or in unwanted chemical changes to the components.